Definition of inflection in English:

noun

There are inflexions for number and tense, the vocabulary is Latin or Germanic for the most part, with all the baggage those words bring with them.

To learn the languages with inversions, it is enough to know the words and their inflections; to learn the French language, we must also retain the word order.

In many hymns (but not all) we have substituted second person plural pronouns and verbal inflections for second person singular ones, but only where this leaves the poetic and rhyming schemes of the hymns unaltered.

The second line became one of the most distinctive features of all New Orleans brass band parades and even of the music itself as the extra musical inflection became an intrinsic element of the Crescent City sound.

A flat, natural, or sharp sign can be placed above it, to indicate a chromatic inflection of the upper note.

In the second period, Balada's music was very abstract and dramatic, without melodic inflection and with a heavy reliance on avant-garde effects.

Derivatives

inflectional

Over time, synthetic languages have become more analytic, with the effect that inflexional morphology has repeatedly been simplified.

And as for the genitive form, it is formed by an inflectional process so productive that it applies to absolutely every new noun added to the language, and they can't possibly be serious about blocking it.

Every so often, though, an inflectional form is closely tied to one particular construction, and then it's tempting to identify the form with the construction (and with the semantics for the construction).

inflectionless

But it's Jazz's rumbling rapping that's become the band's trademark; inflectionless, existential rhyming that hovers over the thumping beats, anchoring the music with some unashamed profundity.

It's hard to describe the emotional effect those inflectionless beeps have on true fans, although they're more than happy to talk about it between themselves on dozens of discussion boards that have appeared on the internet.

Beck's voice is a blunt, inflectionless tool, but his somnambulant tone conveys a creepy sense of resigned ennui that will bring most listeners down but still draw them back for more.

Origin

This comes from the Latin flectere ‘to bend’. The electrical flex (early 20th century) is a shortening of flexible cord or cable, flexible being late Middle English and from the same source, as is deflect (mid 16th century) ‘bend away’. An inflection (Late Middle English) was originally an act of bending inwards, gaining its grammatical sense in the mid 17th century. Flexitime has been being worked, by those lucky enough to get it, since the 1970s.